PLATE I. 



Fig. Page. 



Agnostus fissUS, Lundgren. 3 



1. Complete individual, somewhat compressed laterally. Menevian; Nine Wells, St. David's. 



Sedgwick Museum, Cambridge. 

 2,3. Heads. Menevian; near Nine "Wells, St. David's. Sedgwick Museum, Cambridge. 



Agnostus punctuosus, Angelin. 1 



1. A.somewlial flattened specimen. Menevian; Porth-y-rhaw, St. David's. Sedgwick Museum, 



Cambridge. (Figured by Hicks as Agnostus scarabssoides, Quart, Journ. Geol. Sue., 



vol. xxviii, pi. v, fig. 8.) 

 5. Tail of a young individual. Menevian; Porth-y-rhaw, St. David's. Sedgwick Museum, 



Cambridge. (Figured by Hicks as Agnostus scutalis, Quart, Journ. Geol. Soc, vol. 



xxviii, pi. v, fig. 9.) 

 (i. Tail of a still younger individual. Menevian; Porth-y-rhaw, St. David's. Sedgwick 



Museum, Cambridge. (Figured by Hicks as Agnvntus scidalia, Quart, Journ. Geol. 



Soc, vol. xxviii, pi. v, tig. 10.) 



Agnostus davidis, Salter. G 



7. One of Hieks's types. Menevian ; Portb-y-rhaw, St. David's. Sedgwick Museum, Cam- 



bridge. (Figured by Hicks, Quart. Journ. Geol. Soc, vol. xxviii, pi. v, fig. 2.) 



Agnostus exaratus, Gronwall. 6 



8. Complete specimen, much compressed laterally. Menevian; Porth-y-rhaw, St. David's. 



Sedgwick Museum, Cambridge. (Figured by Hicks as Agnostus scutalis, Quart. Journ. 

 Geol. Soc , vol. xxviii, pi. v, fig. 12.) 



9. A more incomplete but much better preserved specimen. Menevian ; St. David's. Sedgwick 



Museum, Cambridge. 



10. Tail and thorax. Menevian ; near Nine Wells, St. David's. Sedgwick Museum, Cambridge. 



AgnOStUS reticulatuS, Angelin. 8 



11. Complete specimen. Lower Maentwrog beds ; Dolgelly. British Museum, no. I. 7343. 



AgnOStUS pisiformis, Linnaeus. !> 



12. Copy, enlarged to five diameters, of Tullberg's figure, Om Agnostus-iirtvrmi, pi. ii, fig. 14a, b. 



Agnostus pisiformis, var. obesus, Belt. 9 



13. Form with comparatively narrow pygidial axis. Lingula Flags ; Tret'garu Bridge, Haver- 



fordwest. Collected by Mr. V. M. Turnbull. Sedgwick Museum, Cambridge. 



14. Form with pygidial axis much swollen; the head is very imperfectly preserved and con- 



sequently does not show the groove in front of the glabella. Lingula Flags; Trefgarn 

 Bridge, Haverfordwest. Collected by Mr. V. M. Turnbull. Sedgwick Museum, 

 ( Jambridge. 



AgnOStUS trisectus, Salter. 10 



15. A large specimen, with the details of the surface well preserved. Upper Lingula Flags; 



I >g >l' ddu, Criccieth. Collected by Mr. W. G. Fearnsides. Sedgwick Museum, Cam- 

 bridge. 

 L6. A. somewhat flattened head. Upper Lingula Flags ; Moel G-ron. Sedgwick Museum, Cam- 

 bridge. 



All the figures are \^v\'v times the natural size. 



